Railway signal control system for single track railways



Nov. 18, 1952 w. v. GRDSJEAN RAILWAY SIGNAL CONTROL SYSTEM FOR SINGLE TRACK RAILWAYS Filed June 4, 1948 2 SHEETS-SHEET l A? N 2 @w 7 Sm. 2 m n m u m H m n m H m m wm U 1 m m E llll ll 1111111111 L F! lI WN w NS NN QJ \N M mm i X w m\ IN V TOR. Wilbur V pos am.

H15 ATTORMEV Patented Nov. 18, 1952 RAILWAY SIGNAL CONTROL SYSTEM FOR SINGLE TRACK RAILWAYS Wilbur V. Grosjean, Omaha, Nebr., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania Application June 4, 1948, Serial No. 31,070

10 Claims.

My invention relates to a railway signal control system, and particularly to a control system for signals for governing trafiic movements in opposite directions over a stretch of single track railway.

In a railway signaling system of the wellknown absolute permissive block type for a stretch of single track railway which is provided with passing sidings spaced along the single track, two pairs of head block signals, each comprising an entering and a leaving signal, are commonly employed for each passing siding for governing traiiic movements in opposite directions, and are placed one pair adjacent each end of each passing siding. One o more pairs of intermediate signals for governing trafiic movements in opposite directions are also employed between consecutive passing sidings. A polarized line relay, which may be of the retained neutral type, is commonly employed for controlling each of the head block and intermediate signals, so that two such relays are used for each pair of signals.

One feature of my invention is the provision of an arrangement in which each pair of signals for governing traffic movements in opposite directions such, for example, as each pair of head block signals and each pair of intermediate signals in absolute permissive block systems, is controlled by two neutral line relays and one polarized relay of the retained neutral type. the neutral line relays is normally energized, whereas each polarized relay is normally deenergized. Each polarized relay becomes energized in multiple with either one of the associated neutral line relays when the other associted neutral line relay becomes deenergized in response to an approaching train.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

The accompanying drawings, Figs. 1a and 1b, when placed end to end, with Fig. 1a on the left, constitute a diagrammatic view showing one form of apparatus embodying my invention, in which a stretch of single track railway is provided with passin sidings spaced along the single track railway, and in which two pairs of head block signals ar employed for each passing siding and are placed one pair adjacent each end of each passing siding, and two pairs of intermediate signals are employed between consecutive passing sidings, for governing trafiic movements in opposite directions; and in which each pair of signals is controlled by two normally energized neutral line relays and by one normal- Each of 2 1y deenergized polarized relay of the retained neutral type.

Similar reference characters refer to similar parts in each of the drawings.

In each of the drawings, the contacts operated by the various relays are identified by numbers, each such number having a distinguishing prefix from which it is separated by a dash when the associated contact is shown apart from the relay by which it is operated. The prefix for each of these contact numbers comprises the reference character for the respective relay by which the associated contact is operated. For example, contact 3H-39, shown in the lower right-hand portion of Fig. 1a in the lighting circuits for signal 45, is identified by the number 39 separated by a dash from the prefix 3H which is the reference character for relay 3H by which this contact is operated.

Referring further to the drawings, a portion of a single track railway is shown provided with a passing siding X, and also with a second passing siding W, only a portion of which is shown. In order to simplify the drawings, each track, comprising two parallel series of track rails, is represented by a single line.

A portion of the single track railway, shown in the drawings, is divided by insulated joints H to form sections ab, bc, c--d, d-e, ef, f-g, g--h, and h-i. Each of these track sections is provided with a track circuit including a suitable source of current, such as a battery l2, connected across the rails adjacent one end of the section, and a track relay, designated by the reference character T with a distinguishing prefix, connected across the rails adjacent the opposite end of the section. A track relay, designated by the reference character IT, is also shown in Fig. 1a to the left of point and a track relay [GT is shown in Fig. 1b to the right of point i.

Adjacent each end of each of the passing sidings is a pair of head block signals for governing traffic movements in opposite directions. Signals IS, 48, and 93, which govern trafiic movements away from the passing sidings, are known as leaving signals, whereas signals 28, 3S, and IDS, which govern trafiic movements toward the passing sidings, are known as entering signals. Two pairs of intermediate signals SEE-58 and 1S3S govern traffic movements in opposite directions between the two consecutive passing sidings. Signals 28, AS, 65, 8S, and HIS govern trafilc movements toward the right, as shown in the drawings, which I shall assume is the eastbound direction, whereas signals I S, 38, 5s, 18, and 9S govern traflic movements in the opposite or westbound direction. The signals may be of any suitable design, such, for example, as the color light type shown in the drawings, each of which comprises a green or clear lamp G, a yellow or caution lamp Y, and a red or stop lamp R.

Each of the signals has a neutral line control relay, designated by the reference character H with a numerical prefix which is the same as the prefix in the reference character for the associated signal. Each of the neutral line control relays H is energized by current of normalor re"- verse polarity according to traffic conditions in advance of its signal.

Each pair of signals has also a polarized control relay of the retained neutral type, designated by the reference character HD with a prefix which comprises the prefixes in the reference characters for the associated pair of signals. Each of the polarized relays HD is normally deenergized, but at times is connected in multiple with a given one of the associated neutral relays through a back contact of the other neutral relay and a front contact of the given neutral relay. At other times, each of the polarized relays is connected in multiple with the other associated neutral relay through a back contact of the given neutral relay and a front contact of the other neutral relay.

A polechanger relay, designated by the reference character DP with a corresponding numerical prefix, is provided for each pair of head block signals, and is controlled by the neutral line control relay for the associated entering signal and by a front neutral contact and a normal polar contact ofthe associated polarized relay.

A slow release directional stick relay, designated by the reference character SR with a numerical prefix corresponding to that of its sig nal, is provided for each intermediate signal. Each of the directional stick relays is controlled 'to become energized when a train enters the first section in the rear of its signal while the neutral control relay for its signal is energized.

Each pair of head block signals is controlled by the associated polarized relay and by the associated neutral control relays. Each pair of intermediate signals is controlled by the associated directional stick relays as well as by the associated polarized and neutral control relays.

Having described, in general, the arrangement and control of the apparatus shown by the accompanying drawings, I shall now describe in detail, its operation;

As shown by the drawings, all parts of the apparatus are in their normal condition, that is, all track sections are unoccupied, and therefore all track relays are energized; each of the neutral line control relays is energized, and each of the polarized control relays is deenergized; therefore, each of the signals is unlighted; and each of the relays SDP, HlDP, 58R, 68R, TSR, and 88R is deenergized.

The circuit by which relay 21-1 is energized by current of normal polarity passes from terminal B of a suitable source of current, through the front point of contact I3 of relay H, contact 4T-M, contacts I5 and 16 of relays ST and 2T, respectively, winding of relay 2H, and the front point of contact ll of relay H, to terminal N of the same source of current. Relays 3H and Hill are also energized by current of normal polarity in similar circuits.

The circuit by which relay 6H is energized by current of normal polarity passes. from terminal B, through the back point of contact 5SR-23. front point of contact 24 of relay 6H, contacts 25 and 26 of relays ST and 4T, respectively, winding of relay 4H, and the front point of contact 21 of relay 6H to terminal N. Relays IH, 6H, ll-I, and 9H are energized by current of normal polarity in circuits which are similar tothe circuit just traced for relay 5H.

Relay SE is energized by current of reverse polarity passing from terminal B, through the back point of contact 36 of relay 3DP, winding of relay 5H, contacts 35 and 34 of relays 5T and AT, respectively, and the back point of contact 33 of relay BDP to terminal N. Relay 8H is also energized by current of reverse polarity in a circuit which is similar to the circuit just traced for relay 5H.

I shall assume that an eastbound train causes relay EH to become'deenergized. Relay IH, upon becoming deenergized, causes relay 3H to become energized'by current of reverse polarity in a circuit which is the same as the circuit previously described for this relay except that it includes the back points of contacts 18 and 22 of relay lI-I instead of the front points of these contacts.

With. relay IH deenergized, relay I-2HD is now connected through the front point of contact 37 of relay 2H and the back point of contact 38 of relay IH in multiple with the winding of relay 2H in the circuit previously traced for relay 2H, and is energized by current of normal polarity. With relay l-ZHD energized by current of normal polarity, and with relay IH deenergized, lamp G of signal 28 is now lighted by current passing from terminal B, through contact 39 of relay IH. front point of contact 40 of relay l-ZHD, contact 4! of relay i-ZHD closed in its normal position, and lamp G of signal 28 to terminal N.

When the eastbound train deenergizes track relay IT, relay 3H becomes deenergized because of the opening of contact IQ of relay IT. Relay 3H, upon becoming deenergized, connects relay 3-HD through the front point of contact 31 of relay l-I and the back point of contact 38 of relay SH in multiple with the winding of relay 4H. With relay 3H deenergized, and relay 3-4HD energized by current of normal polarity, lamp G or signal 38 now becomes lighted by a circuit which is similar to the circuit previously traced for lighting lamp G of signal 2S.

When the train enters section ab, causing relay 2T to become deenergized, relay 21-1 in turn also becomes deenergized because of the opening of contact iii of relay 2T inthe circuit previously traced for relay 2H. Relay I-2HD, which is connected in multiple with the winding of relay 2H, also becomes deenergized by the opening of contact i6 of relay 2T.

With relay I H still deenergized because of a portion of the train still being in the section West of signal 2S, and with relay l-ZHD now deenergized, lamp G of signal 28 becomes extinguished and lamp R of this signal becomes lighted by a circuit passing from terminal B, through contact 39 of relay IH, the back point of contact All of relay I-ZHD, and lamp R of signal 2S to terminal N. With relays 2H and I-ZHD both deenergized, lamp R of signal IS now becomes lighted by a circuit which is similar to the circuit just traced for lamp R of signal 23.

When the train leaves the first section west of signal 28, permitting relay lT to again become energized, relay IH becomes.v energized by current of normal polarity. Relay l-ZHD is now connected in multiple with the winding of relay IH through the front point of contact 38 of relay III and the back point of contact 31 of relay 2H. With relay 2H deenergized, and with relay l-ZHD now energized by current of normal polarity, lamp G of signal IS becomes lighted by a circuit which is similar to the circuit previously traced for lamp G of signal 28.

When the train enters section cd, deenergizing relay 4T, relay 4H becomes deenergized because of the opening of contact 26 of relay 4T. Relay 3-4HD, which is connected in multiple with relay 4H, also becomes deenergized by the opening of contact 26 of relay 4T. With relays 3H and 3-4HD both deenergized, red lamp R of signal 48 is now lighted. As long as any portion of the train remains on section b-c, relay 3-4I-ID will remain deenergized, and therefore, with relay 4H deenergized, lamp R of signal 35 will be lighted by a circuit which is similar to the circuit previously described for signal 25.

Relay 4T, upon becoming deenergized, also deenergizes relay 5H, causing relay E-GHD to be connected through the front point of contact 31 of relay 6H and the back point of contact 38 of relay 51-1 in multiple with the winding of relay 6H. With relay 5H deenergized, and with relay 5-6HD energized by current of normal pclarity, lamp G of signal 68 becomes lighted by its circuit passing from terminal B, through the back point of contact 45 of relay 5H, back point of contact ESE-46, front point of contact 41 of relay 5-6HD, contact 43 of relay E-GHD closed in the normal position, and lamp G of signal 68 to terminal N.

With relay 5H deenergized, relay 1H is also deenergized because of the opening of contact 29 of relay SE at its front point. With relay 1H deenergized, relay l-BHD is connected through the front point of contact 3'! of relay 8H and the back point of contact 38 of relay (H in multiple with the winding of relay 8H. With relay 1H deenergized and with relay 'l-BHD energized by current of reverse polarity, lamp Y of signal 88 is lighted by a circuit passing from terminal B, through the back point of contact 45 of relay TH, back point of contact TSR-45, front point of contact 4? of relay 'l-8HD, contact 48 of relay I-BHD closed in its reverse or righthand position, as shown in the drawing, and lamp Y of signal 88 to terminal N.

With relay IH deenergized, relay GE is also deenergized because of the opening of contact 29 of relay 1H at its front point. With relay 9H deenergized, relay S-IOHD is connected in multiple with the winding of relay lElI-I through the front point of contact 3'! of relay IIJH and the back point of contact 38 of relay 9H. With relay 9H deenergized and with relay 9-l9HD energized by current of normal polarity, lamp G of signal IDS becomes lighted by a circuit which is similar to the circuit previously traced for lamp G of signal 28.

Relay S-lfiHD, upon becoming energized by current of normal polarity, completes a circuit for energizing relay lllDP, this circuit passing from terminal 13, through contact 53 of relay IOI-I, contacts 54 and 55 of relay S-IBHD, and the Winding of relay liiDP to terminal N. With relay lllDP thus energized, relay 8H becomes energized by current of normal polarity in a circuit which is similar to the circuit previously described for this relay except that it includes 6 the front points of contacts 33 and 36 of relay IODP instead of the back points of these contacts. gized by current of normal polarity, the yellow lamp of signal 88 becomes extinguished, and its lamp G becomes lighted.

When the train enters section d-e, deenergizing relay 5T, relay GSR becomes energized by its pickup circuit passing from terminal B, through the front point of contact 49 of relay 6H, contacts 5T-56 and 5SR-5'l, and the Winding of relay BSR to terminal N.

When the train leaves section b-c, permitting relay 3T to become energized, relay 3H again becomes energized by current of normal polarity in its circuit previously described. With relay 4H deenergized, relay 3-4HD is now connected in multiple with the winding of relay 3H through the front point of contact 33 of relay 3H, and the back point of contact 31 of relay 4H. With relay 4H now deenergized and relay 3-4HD energized by current of normal polarity, green lamp G of signal as becomes lighted. With relay 3H now energized, the circuit for lamp R of signal 4S is opened at contact 311-39, so that signal 48 becomes extinguished.

With relay 3H energized and relay 3-4HD energized by current of normal polarity, relay 3DP becomes energized by a circuit which is similar to the circuit previously traced for relay IUDP.

When the train leaves section c-d, so that relay 4T again becomes energized, relay 2H becomes energized by current of reverse polarity in a circuit which is similar to the circuit previ-- ously traced for this relay except that it includes the back points of contacts 13 and ll of relay 4H instead of the front points of these contacts. With relay 2H energized, contact 42 of this relay Opens the circuit for lamp G of signal IS, causing lamp G of signal IS to become extinguished.

When the train enters section ef, deenergizing relay 6T, relay 6H becomes deenergized because of the opening of contact 25 of relay 6T. With relay 5H deenergized, and with relay 5H remaining deenergized as long as any portion of the train remains in section d-e, relay S-BHD is now deenergized. Relay 6H, upon becoming deenergized, opens the pickup circuit previously traced for relay BSR, which however now remains energized by its stick circuit passing from terminal B, through the back point of contact 69 of relay 6H, contact 58 of relay BSR, contact ESE-53', and the winding of relay GSR to terminal N. With relays 5-6HD and 5H deenergized as long as any portion of the train remains in section d-e, lamp R, of signal 68 will be lighted by a circuit passing from terminal 13, through the back point of contact 45 of relay 5H, back point of contact ESR-M'i, back point of contact til of relay 5-51-11), and lamp R of signal SS to terminal N. Lamp R of signal 53 is now lighted by a circuit passing from terminal B, through the back point of contact 49 of relay 6H, front point of contact ESE-50, and lamp R of signal 55 to terminal N.

When the train leave section dc, permitting relay 5T to again become energized, relay 4H becomes energized by current of reverse polarity passing from terminal B, through the front point of contact 683-28, back point of contact 21 of relay 3H, winding of relay ll-I, contacts 26 and 25 of relays AT and ET, respectively, and the back point of contact 245 of relay 6H to terminal N. Relay 4H, upon opening its contact 31 at the With relays 8H and 'l-BHD now ener-- back. point, deenergizes' relay 3-41-11), and upon opening its back contact Ali-42, extinguishes signal 38. With relay 3-4HD deenergized, relay 3DP becomes. deenergized onaccount of the opening of contact 54 of relay 3-4HD. Relay H is therefore now again energized by current of reverse polarity in its circuit previously described. Relay fi-EHD is now connected through the front point ofcontact 38 of relay 5H and the back point of contact 31 of relay BE in multiple with the winding of relay 5H, so that relay 5-6HD is now also energized by current of reverse polarity.

When the train enters section fg, relay 88R becomes energized by a pickup circuit which is similar to the pickup circuit previously traced for relay 65R.

When the train enters section g-h, relays 8H and T-SI-ID become deenergized because of relay 8T becoming deenergized. With relay 8H. deenergized, the pickup circuit for relay BSR becomes opened, but relay BSR then remains energize'd by its stick circuit which is similar to the stick. circuit previously traced for relay BSR. Lamps R: of signals IS and 85 are now both lighted by circuits which are similar to the circuits. previously traced for lamps R of signals 58 and 6S.

When the train leaves section f-g, permitting relay IT to again become energized, relay 6H becomes energized by current of reverse polarity in a circuit which is similar to the circuit previously traced for energizing relay 4H by current of reverse polarity. Relay 5-6HD, therefore, becomes deenergized, causing signals 58 and ES to be extinguished. With relay 6H now again energized, relay 4H again becomes energized by current. of normal polarity in the circuit previously traced for this relay. Relay 6H, upon becoming energized, opens the stick circuit previously traced for relay BSR, causing relay BSR to again be deenergized.

When the train enters section h-i, the operation of the apparatus associated with signals 98 and MS, and the lighting of signal IBS, will be similar to that previously traced in connection with the apparatus associated with signals IS and 2S and the lighting of signal 28 when the train deenergized relay IT.

It is believed that, in view of the foregoing description of the operation of apparatus. embodying my invention when an eastbound train moves over the stretch of track shown in the drawings, the operation of the apparatus for any other possible trafiic movement can be readily traced by referring to the drawings.

Although -I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing. from the spirit and scope of my inventi'Ol'l;v

Having thus described my invention, what I claim is:

1. In a control system for signals arranged in pairs for governing traflic movements in opposite directions over a stretch of single track railway, the combination comprising, a neutral line control relay for each of said signals each controlled by tra-fiic conditions in advance of its signal, a polarized relay for each of said pairs of signals, means controlled in part by each of said neutral line control relays in its deenergized condition for connecting the associated polarized relay in multiplewith the.v other neutral line. control relay for the same pair of signals, and means includingcontacts controlledby each of said polarized. relays for controlling the associated pair 7 of signals.

2. In a control system for signals arranged in pairs for governing trafiic movements in opposite directions over a; stretch of single track railway, the combination comprising, a neutral line control rel'ayfor. each of said signals each controlled by traffic conditions in advance of its signal, a polarized relay for each of said pairs of signals, means controlled by each of said neutral line control relays in its deenergized condition for energizing the associated polarized relay if the other neutral line control relay for the same pair of signals is energized, and means including contacts controlledby each of said polarized relays for controlling, the associated pair of signals.

3:. In a control system for signals. arranged in pairs for governing traffic movements in opposite directions over a stretch of single track railway, the combination comprising, a neutral line control relay for each of said signals'each controlled by trafiic conditions in advance of its signal, a polarized relay for each of said pairs of signals, means controlled by each of said neutral line control relays in its deenergized condition for energizing the associated polarized relay if the other neutral line control relay for the same pair of signals is energized, and means controlled by each of said polarized. relays and by back contacts of the associatedpair of neutral line control relays for controlling the associated pair of signals.

4. In a control system for signals arranged in pairs for governing trafiic movements inopposite directionsover a stretch of single track railway, the combination comprising, a neutral line control relay for each of said signals each controlled by trafiic conditions in advance of its signal, a polarized relay for eachof said pairs of signals, means controlled by each of said neutral line control relays in its deenergized condition for energizing the associated polarized relay if the other neutral line control relay for the same pair of signals is energized, means, controlled by each of said polarized relays and by a back contact of one of the associated neutral line control relays for controlling the Signal for the other associated neutral line control relay, and means including a back contact of said other associated neutral line control relay for controlling the signal for said one associated neutral line control relay.

5. In combination, a pair of signals located adjacent each other for governing trafiic move' ments in opposite directions on a single track railway, a neutral line control relay for each of said signals each controlled by traffic conditions in advance of its signal to be energized by current of normal or reverse polarity, a polar ized relay of the. retained neutra1 type, means controlled by a front contact of a given one of said neutral relays and by a back contact of the other neutral relay for connecting said polarized relay in multiple with said given neutra1 relay, means controlled by a front contact of said other neutral relay and by a back contact of said given neutra1 relay for connecting said polarized relay in multiple with said other neutra1 relay, means controlled by said polarized relay and by a back contact of said given neutral relay for controlling the signal associated with said other neutral relay, and means controlled by said polarized relay and by a back contact of said other neutral relay for controlling the si nal associated with said given neutral relay.

6. In combination, a pair of signals located adjacent each other for governing trafiic movements in opposite directions on a single track railway, a neutral line control relay for each of said signals each controlled by trafilc conditions in advance of its signal to be energized by current of normal or reverse polarity, a polarized relay, means controlled by a back contact of a given one of said neutral control relays for connecting said polarized relay in multiple with the other neutral control relay, means controlled by a back contact of said other neutral control relay for connecting said polarized relay in multiple with said given neutral control relay, and means controlled by said polarized relay and by said neutral control relays for controlling said pair of signals.

7. In combination, a pair of signals located adjacent each other for governing traflic movements in opposite directions on a single track railway, a neutral line control relay for each of said signals each controlled to be energized by current of normal or reverse polarity, a polarized relay, means controlled by each of said neutral control relays in its deenergized condition for connecting said polarized relay in multiple with the other neutral control relay, and means controlled by said polarized relay and by said neutral control relays for controlling said pair of signals.

8. In a control system for signals arranged in n pairs for governing trafllc movements in opposite directions over a stretch of single track railway, the combination comprising, a neutral line control relay for each of said signals each controlled by trafiic conditions in advance of its signal, a polarized relay for each of said pairs of signals, means controlled by each of said neutral line control relays in its deenergized condition and by a front contact of the other neutral line control relay for the same pair of signals for energizing the associated polarized relay, and means controlled by each of said polarized relays for controlling each signal of the associated pair of Signals if the neutral line control relay for the other signal of the same pair is deenergized.

9. In a control system for signals arranged in pairs for governing traffic movements in opposite directions over a stretch of single track railway, the combination comprising, a neutral line control relay for each of said signals each controlled by traffic conditions in advance of its signal, a polarized relay for each of said pairs of signals, means controlled by each of said neutral line control relays in its deenergized condition if the other neutral line control relay for the same pair of signals is in its energized condition for energizing the associated polarized relay, and means controlled by each of said polarized relays for controlling each signal of the associated pair of signals if the neutral line control relay for the other signal of the same pair is deenergized.

10. In a control system for signals arranged in pairs for governing trafiic movements in opposite directions over a stretch of single track railway, the combination comprising, a neutral line control relay for each of said signals each controlled by traffic conditions in advance of its signal, a polarized relay for each of said pairs of signals, means controlled by each of said neutral line control relays in its deenergized condition for connecting the associated polarized relay in multiple with the other neutral line control relay for the same pair of signals if said other neutral line control relay is in its energized condition, and means controlled by each of said polarized relays for controlling each signal of the associated pair of signals if the neutral line control relay for the other signal of the same pair of signals is deenergized.

WILBUR V. GROSJEAN.

REFERENCES CITED UNITED STATES PATENTS Name Date Van Horn Nov. 9, 1943 in the Number 

